The new capabilities build on existing links Bing has to both Twitter and Facebook, highlighting the increased importance of meshing search engines with social networking sites. For some queries, input from people's social circle is very valuable and relevant.

Bing Social already had a section for people interested in searching only through public posts and status updates from Twitter and Facebook. Now, Twitter content will appear in Bing News search results.

"Search for a news item and immediately see what people are tweeting on the topic," wrote Betsy Aoki, a Bing senior programme manager, in a blog post.

Meanwhile, Bing now displays a Facebook box in which logged in users can type in a status update and post it to their Facebook profile without leaving the Bing interface.

The feature is now specifically available for "overview" pages in Bing Entertainment, a section of the site that offers information digests on movies, actors, singers and other entertainment categories.

"Whether it's a movie, a video game or even an artist, now you share your thoughts with just one click," Aoki wrote.

Google is also working hard to factor in social signals into some of its queries, and recently gave its Social Search service a revamping, promoting its results from a special section at the bottom of the page into the main results list based on their query relevance and sharpening other features.

While access to Twitter content and feeds seems uniform among search engines, Bing does enjoy preferred status with Facebook, thanks to a partnership between the two companies. That has resulted in Google lacking access to important Facebook functionality that Bing has, like the ability to include in results links to Web sites that one's Facebook friends have "liked."